As shown in FIG. 5, during operation of a DC commutator motor, sparks may be generated between a commutator and a carbon brush, which may cause electromagnetic interference (EMI). To suppress or eliminate EMI, a typical measure is to dispose a structure made of an EMI-absorbing material in the motor and surrounding the commutator. However, this increases the weight of the motor, which is not desirable. In addition, this EMI-suppressing structure and its associated mounting structure make the motor structure more complicated, which leads to a more complex manufacturing process and higher manufacturing costs.